- Patients will be stratified on the basis on their KRAS mutational status. Wild-Type KRAS patients will be randomized to receive either single agent erlotinib 150 mg/day or the combination of erlotinib 100 mg/day plus AZD6244 at 150 mg/day. KRAS mutant patients will be randomized to receive AZD6244 monotherapy at a dose of 75 mg twice per day, or the combination AZD6244 at 150 mg/day plus erlotinib 100 mg/day.